From the moment children say "mine!" by two years of age, objects of possession change progressively from being experienced as primarily unalienable property (i.e., something that is absolute or nonnegotiable), to being alienable (i.e., something that is negotiable in reciprocal exchanges). As possession begins to be experienced as alienable, the child enters "moral space," a socially normative and evaluative space made of perceived values that are either good or less good, and where accountability and reputation begin to play a prominent role. The aim of this chapter is to show the close developmental link between possession and morality. (Contains 1 table.)